Use of ScaleSoftPitzer to calculate deposition, or precipitation, in a reservoir or core material during long term flow.

Approach will be presented in four steps:

1. Determine whether equilibrium, kinetics, or mass transport is controlling, 2. Relate precipitation to the physical variables in the field or laboratory core, 3. Relate the physical variables that affect scale formation or dissolution to space and time in the reservoir or core material, and 4. Combine the two into a single description explicitly and implicitly.

Two physical geometries will be examined algebraically, 1st(left). linear flow as might occur in a laboratory column, and 2nd(right). radial flow as might ideally represent flow into or out from a well in a reservoir. Pictorially, these can be represented as follows:

Two flow regimes will be considered for each geometry: A. no gas phase present, as is common with laboratory cores or in deep reservoirs at pressure, and B. with a gas phase is present. The difference is important to CaCO3, FeCO3, FeS, etc., but will no direct effect upon BaSO4, CaSO4’s, NaCl, etc.

Objective: Express the fractional change in porosity, n/n, in terms of flow conditions, brine composition, and time. Specifically, the calculation of n/n can be considered to be composed of four parts, illustrated here for calcite deposition or dissolution:

Summary of approach: the precipitation of, e.g., calcite, d(Ca2+,M), will be expressed as a function of pressure change, dP(psi), which will be expressed in terms of flow rate, Q(m3/s, or B/d) and reservoir properties, such as permeability, k(m2, or md) and porosity.

1. Relate kinetics and mass transport. First, estimate the average distance, or time, that brine will flow for half of the amount that can precipitate to precipitate, i.e., t1/2, and from this show that equilibrium is generally fast compared with reservoir flow.

The heterogeneous mass transport equation for precipitation in the presence of solid core material can generally be modeled with a mass transport-type equation. Calcite, CaCO3, will be used as an example precipitate material, wherein the number of moles of calcite precipitated per liter of brine, d(CaCO3), is equal to the change in the molarity of calcium ions, d(Ca2+,M) per second, dt(s):

Where km(cm/s) is a mass transfer coefficient for the ions in solution and can be estimated by any many dimensionless groups, e.g., the Sieder and Tate heat/mass trasfer analogy, Asolid(cm2) is the surface area of the solid reservoir material with a corresponding volume of brine, Vbrine(cm3), SSA(cm2/g) is the specific surface area of the reservoir material, rs/w(g/cm3) is the ratio of the solid mass to the corresponding volume of water, solid is the density of the solid, and n is the porosity of the reservoir. k1st order(s-1) is a first order rate constant for precipitation. For illustration purposes, assume solid 2.5 g/cm3, n = 0.25, and km = 0.001 cm/s (a conservative estimate):

k1st order(s-1) 0.0075SSA(cm2/g)

-Typically, when we measure SSA of core material by BET isotherm the value is on the magnitude of ½ to 1.0 m2/g = 104 cm2/g, but a range of values will be examined for radial flow (a similar table would apply to linear flow):

...﻿
Benzodiazepine Long-TermUse and Its Cognitive Effects on Memory
In the 1960’s the drug industry in the United States changed dramatically with the introduction of a new category of drugs called benzodiazepines. Since the dawn of time anxiety has been an issue with people, but before the introduction of benzodiazepines there were much different treatments for anxiety problems. In ancient Greece a cure for men would be to engage...

...RESEARCH BULLETIN
October 2012
Longer-TermUse of Opioids With opioid misuse a top public health problem in the United States, this report examined longer-termuse of narcotics in 21 states and how often recommended treatment guidelines for monitoring injured workers with longer-termuse were followed by physicians. The monitoring included services, such as drug testing and psychological evaluations, which...

...2: Theory Question on Short Term and LongTerm Budgeting.
Yes, I agree that budgeting is the key component in management short and longterm planning. According to the website Thinking Make Easy, “Budgeting is a process of planning, setting goals and defining the objectives of the management that are needed for a given period of time. It is the tool that provides specific direction and achievements for the company”...

...Short Term Finance
What is Short Term Financing?
Short term financing is basically refers to additional money for a business which requires for running its business for short terms which is usually a period of one year. There are some sources of short term finance which are as following:-
Overdraft
Overdraft bank basically means a facility that the bank provides to its customers where the customer is given...

...Introduction
Budgeting is indeed a key component in managing short and longterm planning. To define a broad objective such as wealth maximization is clearly not sufficient to achieve the goal. It is very important for an entity to get into more details over how to work towards the objective. Businesses typically do this by crafting a long-term plan and short-term plan which I will be explaining in details.
Budgeting...

...Psychology
Short term and Longterm memory studies…
Short Term Study…
I have researched a study into short term memory and found the following information which focuses on encoding. The purpose of this study was to find out whether people are able to have better short-term recall for words alone or pictures and words presented together. For the methods of this project the researchers selected 20...

...﻿Management of longterm conditions
This assignment will reflect on an aspect of care in the management of asthma as a longterm condition in the primary care setting. It will specifically focus on patient compliance and how it affects good asthma control. A case study of a 22 year old female patient who suffers from asthma will be used to explore the significance of compliance in the management of asthma and the benefits it can have...

Study Tools

Company

Follow

{"hostname":"studymode.com","essaysImgCdnUrl":"\/\/images-study.netdna-ssl.com\/pi\/","useDefaultThumbs":true,"defaultThumbImgs":["\/\/stm-study.netdna-ssl.com\/stm\/images\/placeholders\/default_paper_1.png","\/\/stm-study.netdna-ssl.com\/stm\/images\/placeholders\/default_paper_2.png","\/\/stm-study.netdna-ssl.com\/stm\/images\/placeholders\/default_paper_3.png","\/\/stm-study.netdna-ssl.com\/stm\/images\/placeholders\/default_paper_4.png","\/\/stm-study.netdna-ssl.com\/stm\/images\/placeholders\/default_paper_5.png"],"thumb_default_size":"160x220","thumb_ac_size":"80x110","isPayOrJoin":false,"essayUpload":false,"site_id":1,"autoComplete":false,"isPremiumCountry":false,"userCountryCode":"US","logPixelPath":"\/\/www.smhpix.com\/pixel.gif","tracking_url":"\/\/www.smhpix.com\/pixel.gif","cookies":{"unlimitedBanner":"off"},"essay":{"essayId":37112386,"categoryName":"Chemistry","categoryParentId":"19","currentPage":1,"format":"text","pageMeta":{"text":{"startPage":1,"endPage":15,"pageRange":"1-15","totalPages":15}},"access":"premium","title":"Use of Scale Soft Pitzer to Calculate Deposition, or Precipitation, in a Reservoir or Core Material During Long Term Flow","additionalIds":[13,157,219,10],"additional":["Health \u0026 Medicine","Health \u0026 Medicine\/Pharmaceuticals","Natural Sciences\/Mathematics","Geography"],"loadedPages":{"html":[],"text":[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]}},"user":null,"canonicalUrl":"http:\/\/www.studymode.com\/essays\/Use-Of-Scale-Soft-Pitzer-To-1445502.html","pagesPerLoad":50,"userType":"member_guest","ct":10,"ndocs":"1,500,000","pdocs":"6,000","cc":"10_PERCENT_1MO_AND_6MO","signUpUrl":"https:\/\/www.studymode.com\/signup\/","joinUrl":"https:\/\/www.studymode.com\/join","payPlanUrl":"\/checkout\/pay","upgradeUrl":"\/checkout\/upgrade","freeTrialUrl":"https:\/\/www.studymode.com\/signup\/?redirectUrl=https%3A%2F%2Fwww.studymode.com%2Fcheckout%2Fpay%2Ffree-trial\u0026bypassPaymentPage=1","showModal":"get-access","showModalUrl":"https:\/\/www.studymode.com\/signup\/?redirectUrl=https%3A%2F%2Fwww.studymode.com%2Fjoin","joinFreeUrl":"\/essays\/?newuser=1","siteId":1,"facebook":{"clientId":"306058689489023","version":"v2.8","language":"en_US"},"analytics":{"googleId":"UA-32718321-1"}}